Lock



Aug,I 4, 1936. G. E. swANsoN Loox Filed Aug.` 16, 1933 v Patented Aug. 4, 1936 UNITED; STATES PATENT FFI-cr.

G E. Swanson, New Britain, Conn. Application August 1o, 1933. serai No. 685,306 voisins. (ci. '1o- 41) My invention relates to that type of lockshaving a. key plug normallylocked against rotation but which is released for rotation upon the' insertioniof a key therein, and an object of my invention, among others, is the production of a lock of this type which shall have means to prevent positioning -of the locking elements to release the key plug by surreptitious and-unauthorized methods.

One form of a lock nl invention and inthe construction and use of whichthe objects herein set out, as well as others, may be attained, is illustrated in the accom :11" drawing in whichv Figure 1, is a view in cent1-a1 lwise section through the cylinder and plug ofv my im# proved lock.

Figure 2 is an end view of the e.

Figure 3 is a. side view of a portion ofv my improved key.

Figure 4 is an isometric viewl of said key...

Figure Sis a view similar to Fig'.ll but showing the key in positionv in the lock.

Figure d is a view similar to Fig. l sho l .11 al modiied form of the invention. Figureisaviewincrosssectiononae denoted by the dotted line l-l of 6.

Figure 8' is a view in cross section. scale larged, through a portion of the cylinder and through the plug illustrating the ach'on of a tumbler in an eiiort to release the plug in unauthorized manner.

Figure 9 is a view similar'to Fig. 'i was@ little different construction.

Figure 10 is an end view of the cylinder d the plug of the lock showing another e ii construction.

modiiied form. 'f'

Figure 12 is a detail view in cross sechon through the cylinder and plug of a lock sho my invention as applied to the so-called .nu n form of tumbler. P

Experienced operators nd it pomible to www tion the locking elements in a lock of the herein illustratedand described without the use of a key, this being accomplished by the tion of a picking tool within the key slot and .t by a succession of blows delivered w., I me structure while pressure is the key plug. The arrangement fo the subject matter of my presentv invention is for the purpose of preventing such unauth of a lock, such structure ill w drawing herein in which the n lthe cylinder of a cylinder type 'of lock, il the key plug of such lock which has a slot i2 to receive a key, and the numeral i3 denotes pin tumblers some of which, as herein shown, are of the spool type of tumblers. All of the parts thus 5 far described, as to their general' arrangement, maybe constructed and arranged in any welllmown manner. It will be understood, however, that my invention is not limited to use in a lock of that l of pin tumbler herein shown, as it l0 y be embodied in other forms of tumbler locksl as in so-called disk locks in which the tumblers operate in a manner similar to pin tumblers for controlling operation of the plug as shown in Fig. 12 of the drawing. l'llhe tumblers, with the l5 exception of one hereinafter described, are arranged in pairs, one member of each pair L= :i located in the cylinder and the other member o f weh pair being l ted in the plug. Springs in the tumbler recesses in the cylinder pr the 2o tumblers toward the key slot I2.

In g my invention into eect I provide a guard which, in the structure herein shown, is composed of two members l4l5 spring p toward the key slot by a springvli. This of construction to that 0f the 19in f blers except that it is longer said tumblers andthe hole ll which receives it is f uw.: to the bottom-of the key slot, as shown in Fig. i, whereas the holes for the other pin tumblers ter minate a short distance above the bottom of said slot so thatfthe guard members and the pin tumblers vno 'n :.1 'v rest in the ...r-m shown in The members of the guard are ol' such te tothe une between mim; is the joint it between the plug and the er of the plug 'i9 in the cylinder when the guard rests on e mttom ot the slot as'seen in --f *w into the slot l2 for the p Y of surrep-a titiously manipulating the tumbler-s to et roe taon of the plug without the use of a hey, the moment the .1' n: 11.1* is m t0 any degree the jbint 2t between the two mrs oi the m t above the joint i8 and it theren fore be imble to rotate the hey plus even though the other me.. be tioned so that the joints between the two With the joint 93. rfv-:1' therefl'@ eectually prevents wrt-1i. of the f .zz-w.; by the use oi a tool so that loch et be ce.: am.: Without the use 0f key.

er to ect or the hey I 55 employ a key of peculiar form such key having a notched lip 2i and a supporting wing 22, these two parts forming a grooved structure with a thumb piece 23 in the end thereof. The lip 2i is provided with notches in a manner common to keys forv operating the tumblers of pin tumblerI locks land a guard releasing notch 24 is formed in the inner end of the lip 2l, between said lip and the thumb piece 23, and as shown in Fig. 4 of the drawing.

In order to permit entrance of this key into the lock a recess 25 is provided `extending length- ,Y tering with the joint I8. As the ke`y reaches its innermost position the notch 24 is located underneath the guard and the latter drops into the notch therebyfregistering the joint between its two members with the joint I3 between the plug and the wall of the opening in the cylinder. The

plug is now released and may be turned by rotating the key in the ordinary manner.

Heretofore, in order to obtain sulcient strength in the key the distance between the deepest notch andthe back of the key is controlling, this being L the weakest part of the key, and this has compelled a key to be made of a certain width in order to provide suincient strength. By the use of myY improved key having the wing 22 the notches in the lip 2l may becut 'deeper which is of advantage in locks of this type.

While I have shown herein the guard as located nearest the front end'of the lock, it will be understood that the guard may occupy the position of Vany lof the tumblers and yet perform its function and, in fact, in some cases, the arrangement may be such that more than one guard may be employed.

and having openings through which the-tumblers l The structures shown in Figs.l 6 and 'I embody 'all of the elements shown in the preceding figures, andin addition thereto I have provided a set of dogging plates located in the joint between the plug 26 and the inner wall of the cylinder 21 and the guard extend, these plates having a slight lateral movement as well as some freedom for endwise movement. 'I'hese plates may be provided in such numbers as may be desired and may be of diierent forms. In a satisfactory arrangement and as herein shown two plates are provided, the plate 2 8 being located in a recess in the vwall of the plug opening and the plate 29 being located in a recess in the outer surface of the plug, the two plates resting one against the other and extending from a point vin front of the guard to a point back of the rear tumbler.

With this arrangement, if an eiort be made to position the tumblers for release of the plug and by the use of means other than a key, and in which operation a lateral pressure is applied to the tumblers by a force applied tothe plug to rotate it, in a manner readily understood by those skilled in the art', as a shoulder'created by the spool shape of the tumblers reaches the joint between the plates, or between the plates and the supporting plug or the cylinder, said plates will move slightly, as shown in Fig. 8, and the shoulder on the plugcontacting with the shoulder thus created by the plates obstructs movement of-'the `tumbler. This permits a slight yielding rotatable movement of the plug which with ordinary pin tumblers would indicate that one set of tumblershas reached the releasing position. With my structure, fhowever, this movement is deceptive and the operator cannot tell just what the position of thetumblers is and it therefore creates a very difficult problem to open the lock with means other than al key, if it does not entirely prevent such unauthorized operation.

In the form of the lock shown in Fig. 9 instead of, the plate 23 a hollowv cylinder 30 'is provided which completely encloses the plug 26, the cylinder, however, performing all of the functions of the plate 28 in the structure of the preceding figures and having a limited rotating movement. In Fig. 10 my invention is shown as applied to one form of an angularly shaped key slot 3| in the plug 32, the releasing notch for the guard member i4 being located in the upper edge of the key which bears the tumbler notches.

Figure 11 shows the application of myidea, to a plug having another form ofangularly shaped key slot 3l in a plug 33 in a manner that will be readily understood from the foregoing description. The structure shown in Fig. 12 illustrates the application of my invention to the well-known form of "disk" tumblers ldcated in the cylinder 35. singlemember, each of a length equal to the diameter of the plug, and as will be readily understood by those skilled in the art, said tumblers normally resting with their ends in different positions inthe slot 33 in the cylinder. 'I'he guard tumbler 36 is also preferably composed of a single member but lis provided with an actuating shoulder 31 as in the case of other tumblers upon which the bit J or notched lip of the key operates. e

It will nbe noted from this structure'that as soon as the key encounters the guard 3S it is raised and thereby prevents rotating movement of the plug 39. However, as the key ,is'fully inserted and the tumblers are all properly positioned, the shoulder 31 ornes opposite anotch in the key, as hereinbefore explained, and the guard 36 is pressed downwardly by its spring to the position shown in Fig. 12 so that'the plug 3.9 may be rotated. y

- It will be noted that the solid portion or the guard 3B is located opposite the key slot as shown in Fig. 12 so that any attempt to insert a picking tool underneath theshou'lder 31 will raise the guard 33 into locking position and thereby prevent any rotating movement of the plug 38.

It will be noted that the key slot 3l in the structure shown in Fig. 10 is of such'angular These tumblersare composed usually of a shape as to prevent the entrance of a picking' tool to the tumblers-behind the guard, the upper and lower portions of the slot being widely enough separated to effect this purpose, and the guard therefore effectually prevents access to the tumblers by such means. The lower portion of the key which is made -of theshape of the slot 3| effects thel same purpose as the wing 22 in the device nrst hereinbefore described, and the same is true of the horizontal portion of the slot 34.l y

In accordance with the provisions of the patent statutes I have described. the principles of operation of my invention, together with the device which I now consider to represent the best embodiment thereof; but I desire to have it understood that the device shown is only illustrative and that the invention may be carried out by other means and applied to uses other than those above set out. v

I claim:

l. A lock including a cylinder, a plug rotatably mounted in said cylinder and having a key slot, anda tumbler mounted in Asaid cylinder and seated substantially at the bottom of said key slot at the outer surface of said plug, said cylinder and plug having betweenv them registering guard openings andra laterally extending recess for the wing of a key, said tumbler extending completely through said plug and being of a length substantially the same as that of the diameter of the plug. x

2. A lock including a cylinder, a plug rotatably y mounted in said cylinder and having a key slot,

and a tumbler mounted in said cylinder and lseated. substantially at the bottom of said key slot at the outer surface of said plug, said cylinder and plug having between them registering guard openings with a recess opening from the key slot at the line of separation between the plug and the cylinder to receive the wing oa key, said tumbler being normally located in said plug with one end flush with\the mouth of the guard opening in the cylinder whereby movement from its normal position will enter it into said opening in the cylinder.

3. A lock including a cylinder, a plug rotatably mounted `in said cylinder and having a. key slot,

and a tumbler mounted in said cylinder and vseated substantially at the bottom of said key the outer surface of the plug, said cylinder and plug having between them a. recess for the wing of a key, said recess extending laterally from said key `slot.

5. A lock including a cylinder having a guard 5 opening and tumbler openings, a plug rotatably mounted in said cylinder and having a key slot, tumblers mounted in said cylinder and plug, a recess at the line of separation between the plug and cylinder for the wing of a key, said recess extending laterally from said key slot, and a guard member normally located in said plug with plug, and a guard member normally located in said plug with one end ush with the mouth of the guard opening in the cylinder and with its opposite end seated in said recess whereby movement from its normal position will enter it into said opening in the cylinder. g

A7. A lock including a cylinder having a guard opening and tumbler openings, a plug rotatably mounted in said cylinder and having an angularly shaped key slot comprising a horizontal and a vertical portion extending parallel with each other and adapted to receive a similarly shaped key having a releasing notch cutting through its vertical portion and bridged by said wing, tumblers mounted in said plus, and a guard member normally located in said plug with one end flush with the mouth of the guard opening in the cylinder whereby movement from its normal posio tionwill enter it into said opening in the cylinder,

said guard being adapted to enter said notch to s release said cylinder.

GUNNARD E. SWANSON. 

